import { all, run } from "../db";

const DAY_CHARS = 10;
const MAX_REPORT_DAYS = 90;

/** One upsert per tool call; errors are counted too, since they still consume capacity. */
export async function recordToolUsage(accountId: string, tool: string, failed: boolean): Promise<void> {
  try {
    await run(
      `INSERT INTO mcp_usage_daily (account_id, day, tool, calls, errors) VALUES (?, ?, ?, 1, ?)
       ON CONFLICT (account_id, day, tool) DO UPDATE SET calls = calls + 1, errors = errors + excluded.errors`,
      accountId,
      new Date().toISOString().slice(0, DAY_CHARS),
      tool,
      failed ? 1 : 0,
    );
  } catch (error) {
    console.error("MCP usage metering failed", error);
  }
}

export type UsageRow = { day: string; tool: string; calls: number; errors: number };

export async function usageForAccount(accountId: string, days: number): Promise<UsageRow[]> {
  const since = new Date(Date.now() - Math.min(days, MAX_REPORT_DAYS) * 86_400_000).toISOString().slice(0, DAY_CHARS);
  return all<UsageRow>(
    "SELECT day, tool, calls, errors FROM mcp_usage_daily WHERE account_id = ? AND day >= ? ORDER BY day DESC, tool",
    accountId,
    since,
  );
}